[zamadatix]

Edit: This is in response to the "fleet of Pi's" question, obviously a Mac Mini is not going to be cheaper to rent than a single Pi! The aforementioned VPS route is the better way to go for that case.

Scaleway will give you an 8 core 16GB RAM 256GB SSD M1 Mac Mini for €0.1/h. It may not sound like much of an increase from core count but it is ~10x faster for multicore which means it probably comes out on top for perf/€, perf/Watt, and total perf compared to a rack of Pi 4's for any such distributed ARM use case.

For pure traditional cloud a Graviton2 instance on AWS is probably more green, albeit probably less cost efficient to the user.

[selectodude]

That’s €72/mo. Different price class there.

[zamadatix]

To be clear this isn't an alternative to hosting a single Pi it was in response to the distributed case:

> Maybe there are ARM-specialized, highly distributed tasks for which a fleet of Pis is particularly efficient?

Assuming the task really requires ARM, is perfectly scalable among multiple systems, doesn't require more than 10mbps between the nodes, and doesn't require dedicated control/scheduling nodes (i.e. best case for the Pi's) a fleet in multiples of 10 Pi's per would be $59.90 month each plus the up front cost of the Pi's, power adapters, SSDs, and shipping. And even if you wrote off the up front hardware as on hand it would still be significantly less green to run.